Packing for machinery.



UN ITED STATEE PATENT @FFICE,

PIERRE HOURLIER, OF PARIS, FRANCE, ASSIGNOR TO LAIR LIQUIDE (SOCIETE ANONYME POUR LETUDE ET LEXPLOITATION DES PROCEDES GEORGES CLAUDE), OF PARIS, FRANCE.

PACKING FOR MACHINERY.

No Drawing.

To all whom it may concern Be it known that I, PIERRE HOURLIER, a citizen of the Republic of France, residing at 48 Rue St. Lazare, Paris, in the Republic of France, have invented certain new and useful Improvements Relating to Packing for Machinery, of which the following is a specification.

This invention relates to packing for machinery, and has particular reference to the use of cupped or semi-cupped leather packing for the parts of machines working at low temperatures, such for example as are used in the manufacture of liquid air by processes involving the rapid expansion of compressed air. The pistons and valve stems of such machines are instances of parts that are subjected to low temperatures and require to form a good joint with the guide surfaces over which they move.

I have found that in order to utilize, with out any inconvenience, cupped or semicupped leather packing, such as can be obtained commercially, in apparatus operating at low temperatures such as above mentioned, it is necessary to free the leather, before use, from all fatty matter that it contains.

According to the present invention, therefore, the leather is treated with a fat removing substance. For this purpose I have found it sufficient to use an ordinary solvent for fatty matter, such as ether, benzin and the like. The leather packing, thus prepared, retains almost entirely, at the temperature of liquid air and even at lower temperatures, the same degree of pliability that it possesses at ordinary temperatures. It is also necessary, just prior to putting such fat-freed leather packing into action, to remove all moisture from it, for example by heating it in a stove. Furthermore, and this is one of the great advantages resulting from the invention, I have found that the action of the leather prepared in the manner indicated above is satisfactory to such an extent as to permit of wholly dispensing with the lubrication of the frictional parts or elements of the machine or apparatus in which the leather is used, this applying particularly to the piston cylinders of machines for the expansion of air in liquid air manufacture.

Specification of Letters Patent.

Patented Ame, 1916.

It is true that in the early stages of the development of liquid air manufactureby the method of expanding compressed air in an expansion engine with production of recoverable external work, the idea arose of workmg without the addition of any lubricant when once low temperature conditions were reached, the liquid air formed in the engine cylinder being relied upon to moisten the metal surfaces and itself serve as lubricant. Subsequently the above mentioned method of manufacture of liquid air ,was greatly improved by utilizing the cold of the expanded air for the liquefaction of compressed a1r not destined to be expanded'in 3 the expansion engine, this modified method with the present invention is particularly useful in expansion engines employed in carrying out the method of liquid air manufacture by expansion with external work and liquefaction under pressure for it has been found that by using my specially prepared leather packing, lubrication of the engine cylinder can be entirely dispensed with both on starting and also when the lowtemperature conditions of running are attained. Inter alia, the following advantages are presented :The use of my specially treated leather in the form of cup-shaped piston rings avoids the fracture hitherto liable to occur with metal piston rings and the consequent binding of the cylinder; also, the absence from the cylinder of all lubricant, such as petroleum ether, avoids the inconvenience otherwise liable to result owing to the fact that portions of the lubricant may be carried along into and thus contaminate the liquid oxygen, when, as in apparatus forproducing oxygen or nitrogen by expansion of air with external work and liquefaction under pressure followed by rectification, the exhaust from the expansion engine proceeds to the rectification column.

What I claim and desire to secure by Letters Patent of the United States is 1. Means for preventing leakage between the frictional surfaces of relatively movable parts of machines working at low tempera ture such as that of liquid air, consisting of an unlubricated packing of leather from which the fatty matter has been removed.

2. Means for preventing leakage between the frictional surfaces of relatively movable parts of machines working at low temperature such as that of liquid air, consisting of an unlubricated packing of leather from which the fatty matter and moisture have been removed.

In testimony whereof I affix my signature in presence of two witnesses.

PIERRE HQURLIER. Witnesses; I

W'ILLIAM AUDIBERT, HANSON C. CoXE.

Copies of this'patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

